The present invention relates generally to vents and more particularly, to grease/contaminant containment apparatus for use in conjunction with exit vents.
Vents, particularly powered roof vents, are common on commercial buildings for providing an exit for the ventilation of air from the interior of a building. The air is typically channeled out of the building through duct work. The duct work terminates in an exit vent which is simply an orifice that allows the air to exit the building. An exit vent is typically formed by a duct that extends outward from the surface of the building, with an opening at the end of the duct forming the exit vent.
In some applications, the air to be evacuated is laden with grease or other contaminants. For example, restaurants, use grease in the preparation of food. Some of the grease used escapes into the air within the restaurant and is vented to the exterior of the building, typically by roof vents.
Grease and other contaminants either collect on the sides of the duct forming the vent or exit the vent, along with the air, to settle on surfaces in close proximity to the exit vent. In many situations, there is a contaminant buildup on the exterior of the building around the vent. The primary cause for this being that the contaminants leak out of seams in the fan structure or the linkage between the fan and exit vent structures.
In many instances, vented contaminants are harmful to the building, particularly the roofing surface. Additionally, the contaminants may be flammable and, thereby, create a fire hazard. Under these situations, it is preferred that contaminants be contained and/or collected before they contact the building surfaces.
Traditionally, contaminant collection has involved the use of absorbent pads placed adjacent a roof vent or adjacent to a ventilation fan attached to the duct forming the exit vent. These pads are typically not reusable or recyclable and new pads must periodically be bought and installed. This system is both costly to the environment and to the owner of the ventilation system. Further, although this method collects some of the contaminants, often times the pads are not changed in a timely manner leading to a contaminant buildup. In many instances, the contaminants either flow off the surface of the pad or soak through the pad and onto the surface of the building. In either case, the contaminants come in contact with the surface of the building. Under these circumstances, the pads do not solve the problems of contaminant buildup.
Another proposal to capture and remove contaminants is a trough. However, known structures have a gap between the trough and the surface to which it is attached. The gap allows contaminants to seep through the gap to the exterior surface of the building. In some instances, the trough is not seamless such that contaminants leak through the seams in the trough. In addition to the collection of contaminants, the troughs of the prior art also collect rain water and other debris and, in some cases, the capacity of the trough is not sufficient to hold all of this material, causing an overflow of the trough and onto the surface of the building.
The present invention provides an apparatus for the capture of heavy contaminants, such as grease, from the roof vent of a building. The apparatus of the present invention includes a trough adjacent the duct forming the exit vent. The trough, and possibly the entire body, may be constructed from a seamless piece of material. It is also preferred that the trough surround the exit vent.
The trough is preferably constructed and arranged such that no contaminants exiting the vent can pass between the trough and the duct surface. For example, in accordance with one embodiment of the present invention, the apparatus includes a flange extending into the exit vent. It is preferred that the flange be attached to the interior surface forming the exit vent and, more preferably, that the attachment of the flange is made such that no contaminants can pass between the flange and the interior surface of the duct forming the exit vent. It is also preferred that the flange is constructed and arranged to surround the exit vent.
The apparatus may also include a trough cover. The cover is attached to the trough such that it allows contaminants to pass between the duct forming the exit vent and the cover, and into the trough. The cover may be formed of a plurality of sections and, more preferably, portions of adjacent cover sections overlap.